The present invention is directed to apparatus for the conveyance of waste water or sewage, and more particularly to sewage conveying apparatus including a rotary cutting device and a rotary pump carried on a common drive shaft.
It is a known method to use eccentric worm-gear pumps, which are among available rotating displacement pumps, for the conveyance of waste water or sewage. Eccentric worm-gear pumps have the advantage that the quantity of material they convey, when the speed of rotation of the rotary drive remains the same, is practically independent of the resistance in the delivery pipe, so that the latter can be dimensioned optimally for any desired use. Eccentric worm-gear pumps have the additional advantage that high pressures can be achieved. However, eccentric worm-gear pumps are not capable of handling large solids. For that reason, the suggestion has already been made to connect an eccentric worm-gear pump in series with a pulverizing device that reduces the size of materials drawn in by the eccentric worm-gear pump (see the paper by H. Putz entitled "Abwasserhebeanlagen" in the Fachzeitschrift fur Sanitur, Heizung, Klima, No. 23, volume 35, first edition, Dec. 1980, Berlin). The present invention has the objective of creating an apparatus of the type mentioned at the outset and is distinguished by a compact and simple design.